Relay drive apparatuses that drive a relay to supply electric power to an electronic device have been known heretofore (for example, Patent Literature (hereinafter, referred to as “PTL”) 1. In the relay drive apparatus of PTL 1, a voltage of coil 6 of relay 8 is temporarily increased in a case where relay 8 is turned ON. The voltage of coil 6 is temporarily increased because an operation of relay 8 is likely to become unstable in a case where the relay drive apparatus is used in a high-temperature environment such as a vehicle-mounted charging apparatus, and relay 8 should be surely turned ON even in such cases. In the relay drive apparatus of PTL 1, an ON signal is output to first transistor 3 from first output terminal 2a of control circuit 2 so that first transistor 3 is put into a conduction state. In the relay drive apparatus of PTL 1, the voltage of coil 6 of relay 8 can be temporarily increased in this manner.
Meanwhile, the relay drive apparatus of PTL 1 lowers the voltage of coil 6 to reduce the power consumption after relay 8 is turned ON.
In other words, in the relay drive apparatus of PTL 1, first transistor 3 is maintained in an ON state from time t0 to time t1 as illustrated in FIG. 1. First transistor 3 is turned OFF after time t1 inclusive. In addition, in the relay drive apparatus of PTL 1, the voltage of coil 6 of relay 8 is high from time t0 to time t1 and is low after time t1 inclusive as illustrated in FIG. 2.